Do you know if you have pulseaudio running somewhere in there? I know every time I do a fresh install I have to remove it and reboot. Then things tend to start working, but until I've removed it nothing audio works.

Someone in the forums came up with a suggestion a while back to just rename pulseaudio as it's not very easy to uninstall/remove. This works on all my laptops for a while now, so much so that the first thing I do after a fresh install is execute that command - just in case it's running or being used.